Description
Rare condition with unknown aetiology. In literature there are just case series.
Usually affect 3th-5th decade of life. We know two different types of that pathology:
-Primary (idiopathic); synovial cells undergo metaplastic change to chondrocytes, which than produce multiple clusters of cartilage, giving rise to the characteristic uniform loose bodies
-Secondary to osteochondral defect where osteochondromatosis is thought to arise from a central nidus, such as an osteochondral fragment in trauma, or degenerative disease such as osteoarthritis. Subsequent enlargement results from proliferation of connective tissue cells and cartilaginous metaplasia, and the characteristic loose bodies develop.